Hi Hubbard Brook,
The last week’s temperatures have been a close match with forecasts and the phenology predictions have remained locked on the same dates as this time last week. Forecasts are for the Main bird plot at about 475
m asl. Further details, and the sequence of predictions for this year, are in the enclosure.
Matt
As of 12 May 2020, predicted dates for budburst and 90% completion of leaf expansion are:
21 May and 31 May.
Predicted median dates of Arrival and 1st clutch initiation by Black-throated Blue Warblers are:
13 May and 4 June.

From: Matthew P. Ayres
Sent: Tuesday, May 5, 2020 11:31
To: 'Hubbardbrook@lists.sr.unh.edu' <Hubbardbrook@lists.sr.unh.edu>
Subject: RE: Updated leaf-out forecast for Hubbard Brook
Hi HB,
In case you are interested, here is a comparison of the thermal progression so far for this year compared to expectations for 2020 based on the last 50 years. You can see the flattening and divergence due to
cool temperatures during the last week and expected for the next week.
Matt

From: Matthew P. Ayres
Sent: Monday, May 4, 2020 22:05
To: Hubbardbrook@lists.sr.unh.edu
Subject: Updated leaf-out forecast for Hubbard Brook
Hi HB,
Even more good news if you were hoping for a late spring. The last week has been cooler than forecast and the next 10 days are forecast to be much cooler than average for these dates. As a result, the updated
spring forecast for budburst on the Main bird plot has slipped back a whopping 6 days since last week to 21 May.
Based on our current best phenology models (after Lany et al. 2015), temperatures to date this year, and the 10-day forecast as of
5 May 2020, predictions for budburst on the Main bird plot (490 m asl) are:
·
Budburst = 21 May,
·
90% completion of leaf expansion = 31 May,
·
Median date of arrival and first clutch initiation for Black-throated Blue Warblers = 13 May and 4 June, respectively.
More details in enclosure.
If the current budburst prediction is accurate, it will be about 9 days later than that expected for 2020 (below and page 2 in enclosure).
Feel free to share this with anyone who may be interested. We will aim to provide weekly updates of the forecasts.
Matt
